1. Field of the Invention
This invention relates to an image sensing apparatus using a solid-state image sensor and more particularly to an image sensing apparatus which is arranged such that, in cases where some of the picture elements of the solid-state image sensor is defective due to a flaw or the like, the defect is compensated for by making the defective picture element part inconspicuous.
2. Description of the Related Art
FIG. 1 of the accompanying drawings shows in a block diagram an electronic camera using a solid-state image sensor (hereinafter referred to as CCD). A control circuit 212 includes a CPU which is arranged to control a shutter stop 2 according to the luminance value of a photographing object obtained by a light measuring circuit 13. Then, an image of the object which comes through a lens 1 is projected on the CCD 3. In this instance, the CCD 3 is driven by a driving circuit 10 on the basis of timing pulses generated by a clock pulse generating circuit 11 under the control of the control circuit 212. The driving circuit 10 thus drives the CCD 3 to accumulate the projected image in the form of an electric charge. The accumulated electric charge is read out and sampled by a sample-and-hold circuit 14. The sampled electric charge is converted into a continuous signal and is supplied to a signal processing circuit 4. The signal processing circuit 4 processes the continuous signal to convert it into a video signal. The output of the circuit 4 is then modulated at a recording circuit 5 into a recordable signal form. The signal thus modulated is recorded via a magnetic head 6 on a magnetic sheet 7 which is rotated under the control of a serve circuit 9 and a motor 8.
It is of course desirable that the solid-state image sensor has no defective picture element. However, in the manufacture of the image sensor, the required number of picture elements, the size of an image plane, etc. lower the yield and increase the cost of manufacture. Meanwhile, the manufacturing problem results in some defective element that comes to show a white spot in its corresponding part on the image plane. Such a defective part is not usable as it is and necessitates interpolation with something like a signal portion obtained from a picture element adjacent to the part in question. However, such an interpolating arrangement has presented a problem in terms of practicability as it increases the scale of circuitry arrangement.